Spool assembly with locking mechanism for additive manufacturing system, and methods of use thereof

ABSTRACT

A spool assembly comprising a housing structure, a spool rotatably retained in an interior region of the housing structure, and a sealed sheath encasing the housing structure to define a barrier for the encased housing structure and the rotatably retained spool. The spool assembly further comprises a locking arm disposed outside of the sealed sheath and configured to operably engage the spool through the sealed sheath and through the housing structure in a manner that does not penetrate the sealed sheath, where the locking arm prevents the spool from rotating relative to the housing mechanism when operably engaged with the spool. The locking arm may disengage from the spool in a hands-free manner when the spool assembly is loaded into a bay of an additive manufacturing system.

CROSS-REFERENCE TO RELATED APPLICATION(S)

Reference is hereby made to co-filed U.S. patent application Ser. No.______ (attorney docket no. S697.12-0215), entitled “SPOOL ASSEMBLY FORADDITIVE MANUFACTURING SYSTEM, AND METHODS OF MANUFACTURE AND USETHEREOF”, the disclosure of which is incorporated by reference in itsentirety.

BACKGROUND

The present disclosure relates to additive manufacturing systems forbuilding three-dimensional (3D) parts with layer-based, additivemanufacturing techniques. In particular, the present disclosure relatesto spool assemblies for supplying consumable part and support materialsto additive manufacturing systems.

Additive manufacturing systems are used to print or otherwise build 3Dparts from digital representations of the 3D parts (e.g., AMF and STLformat files) using one or more additive manufacturing techniques.Examples of commercially available additive manufacturing techniquesinclude extrusion-based techniques, jetting, selective laser sintering,powder/binder jetting, electron-beam melting, and stereolithographicprocesses. For each of these techniques, the digital representation ofthe 3D part is initially sliced into multiple horizontal layers. Foreach sliced layer, a tool path is then generated, which providesinstructions for the particular additive manufacturing system to printthe given layer.

For example, in an extrusion-based additive manufacturing system, a 3Dpart may be printed from a digital representation of the 3D part in alayer-by-layer manner by extruding a flowable part material. The partmaterial is extruded through an extrusion tip carried by a print head ofthe system, and is deposited as a sequence of roads on a substrate in anx-y plane. The extruded part material fuses to previously deposited partmaterial, and solidifies upon a drop in temperature. The position of theprint head relative to the substrate is then incremented along a z-axis(perpendicular to the x-y plane), and the process is then repeated toform a 3D part resembling the digital representation.

In fabricating 3D parts by depositing layers of a part material,supporting layers or structures are typically built underneathoverhanging portions or in cavities of 3D parts under construction,which are not supported by the part material itself. A support structuremay be built utilizing the same deposition techniques by which the partmaterial is deposited. The host computer generates additional geometryacting as a support structure for the overhanging or free-space segmentsof the 3D part being formed. Support material is then deposited from asecond nozzle pursuant to the generated geometry during the printingprocess. The support material adheres to the part material duringfabrication, and is removable from the completed 3D part when theprinting process is complete.

SUMMARY

An aspect of the present disclosure is directed to a spool assembly. Thespool assembly includes a housing structure having an interior region, aspool rotatably retained in the interior region of the housingstructure, and a sealed sheath encasing the housing structure to definea barrier for the encased housing structure and the rotatably retainedspool. The spool assembly also includes a locking arm disposed outsideof the sealed sheath and configured to operably engage the spool throughthe sealed sheath and through the housing structure in a manner thatdoes not penetrate the sealed sheath, where the locking arm prevents thespool from rotating relative to the housing mechanism when operablyengaged with the spool.

Another aspect of the present disclosure is directed to a spool assemblyfor use with an additive manufacturing system. The spool assemblyincludes a spool configured to retain a supply of a filament for use inthe additive manufacturing system, and a sealed sheath encasing thespool. The spool assembly also includes a locking arm disposed outsideof the sealed sheath, where the locking arm is configured to operablyengage the spool through the sealed sheath in a non-penetrating mannerwhile in an engaged state to prevent the spool from rotating in thesealed sheath. The locking arm is further configured to be disengagedfrom the spool while in a disengaged state to allow the spool to rotatewithin the sealed sheath. The spool assembly is configured to beinserted into a bay of the additive manufacturing system, and thelocking arm is configured to actuate from the engaged state to thedisengaged state when the spool assembly is inserted into the bay.

Another aspect of the present disclosure is directed to a method forloading a spool assembly to an additive manufacturing system. The methodincludes providing the spool assembly comprising a spool retaining afilament, where the spool is rotatably retained within a sealed sheath(e.g., a bag) of the spool assembly that defines a barrier for theretained spool. The method also includes inserting the spool assemblyinto a bay of the additive manufacturing system, which contacts thelocking arm with at least one slot ledge of the bay, and contacting thelocking arm with a slot ledge of the bay while inserting the spoolassembly into the bay. The method further comprises pressing thecontacted locking arm upward with the slot ledge while inserting thespool assembly into the bay to disengage to the locking arm from thespool, and rotating the spool in the sealed sheath after the lockingmechanism is disengaged from the spool.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top perspective view of an additive manufacturing system inuse with spool assemblies of the present disclosure, where the spoolassemblies are loaded to the additive manufacturing system.

FIG. 2 is a top perspective view of the additive manufacturing system inuse with the spool assemblies, illustrating a process for loading thespool assemblies to the additive manufacturing system.

FIG. 3 is a top right-side perspective view of one of the spoolassemblies.

FIG. 4A-4C are perspective views of the spool assembly, illustrating aprocess for manufacturing the spool assembly.

FIG. 5A is a right side expanded view of the top portion of the spoolassembly, illustrating a locking arm engaged with a spool retainedwithin a sheath.

FIG. 5B is a left side expanded view of the top portion of the spoolassembly, illustrating the locking arm engaged with the spool.

FIG. 6A is a right side expanded view of the top portion of the spoolassembly, illustrating the locking arm disengaged from the spool.

FIG. 6B is a left side expanded view of the top portion of the spoolassembly, illustrating the locking arm disengaged from the spool.

FIG. 7 is a top right-side perspective view of the spool assembly asshown in FIG. 3, with the sheath omitted, and with the locking armdisengaged from the spool.

FIG. 8 is a top left-side perspective view of the spool assembly, withthe sheath omitted, and with the locking arm engaged with the spool.

FIG. 9 is an expanded view of an engagement between the locking arm andthe spool, as taken from the top right-side perspective view of FIG. 8,where the locking arm is shown disengaged from the spool.

FIG. 10 is an expanded view of an engagement between the locking arm andthe spool, as taken from the top left-side perspective view of FIG. 9,where the locking arm is shown disengaged from the spool.

FIG. 11 is a bottom right-side perspective view of the spool assemblywith sheath and a portion of a housing structure omitted.

FIG. 12 is a left side view of a first shell section of the housingstructure, showing an interior side of the first shell section.

FIG. 13 is a right side view of a second shell section of the housingstructure, showing an interior side of the second shell section.

FIG. 14 is schematic illustration of a top corner of the housingstructure engaged with an eyelet seal of the spool assembly.

FIG. 15 is a perspective view of the eyelet seal in use with a guidetube.

FIG. 16 is an exploded perspective view of the eyelet seal and the guidetube.

FIG. 17 is a side view of an alternative spool assembly of the presentdisclosure, which incorporates an alternative housing structure having ahalf-moon structure.

DETAILED DESCRIPTION

The present disclosure is directed to a spool assembly (also referred toas a consumable assembly) for use in an additive manufacturing system,such as an extrusion-based additive manufacturing system. The spoolassembly is an easily loadable, removable, and replaceable containerdevice configured to retain a supply of part or support materialfilament. The spool assembly includes a container portion having a spooland a housing structure, where the supply of part or support materialfilament is wound around the spool.

In one embodiment, the spool assembly also includes a moveable lockingarm that engages the spool through a sheath (e.g., amoisture-impermeable sheath) and a housing structure. The locking armdesirably does not puncture or otherwise penetrate through the sheath topreserve a barrier from ambient conditions (e.g., moisture barrier) inthe container portion. When engaged with the spool, the locking armprevents the spool from rotating, which can otherwise cause the retainedfilament to unravel prior to use in an additive manufacturing system. Asdiscussed below, when the spool assembly is loaded into a bay of anadditive manufacturing system, the locking arm mechanically disengagesfrom the spool in a hands-free manner. This prevents the spool assemblyfrom being used in an additive manufacturing system while the lockingarm remains engaged with the spool.

In another embodiment, the spool is rotatably retained in the housingstructure in a hub-less manner, in that the spool is not supported by ahub mount of the housing structure. Instead, when the spool assembly ispositioned in an upright orientation, the spool rests on bearingsupports (e.g., bearing rollers) located at the bottom of the housingstructure. As discussed below, this reduces frictional resistancebetween the spool and the housing structure while the spool rotates.

FIGS. 1 and 2 show system 10 in use with two spool assemblies 12 of thepresent disclosure, where each spool assembly 12 is an easily loadable,removable, and replaceable container device that retains a consumablefilament for printing with system 10. Typically, one of the spoolassemblies 12 contains a supply of part material filament (“partmaterial spool assembly”), and the other spool assembly 12 contains asupply of support material filament (“support material spool assembly”).However, both spool assemblies 12 may be identical in structure.

As shown in FIG. 1, each spool assembly 12 includes container portion14, guide tube 16, print head 18, and handle 20, where container portion14 retains a spooled supply of a consumable filament. Guide tube 16interconnects container portion 14 and print head 18 to supplysuccessive segments of the filament from container portion 14 to printhead 18. Handle 20 is attached to container portion 14 and allows a userto conveniently grip and carry spool assembly 12. As discussed below,handle 20 is also suitable for storing guide tube 16 and print head 18when spool assembly 12 is not loaded to system 10 (e.g., duringtransportation and storage).

System 10 is an additive manufacturing system for printing 3D parts ormodels and corresponding support structures (e.g., 3D part 22 andsupport structure 24) from the part and support material filaments,respectively, of spool assemblies 12, using a layer-based, additivemanufacturing technique. Suitable additive manufacturing systems forsystem 10 include extrusion-based systems developed by Stratasys, Inc.,Eden Prairie, Minn. under the trademarks “FDM” and “FUSED DEPOSITIONMODELING”. As shown, system 10 includes system casing 26, two bays 28,build chamber 30, platen 32, platen gantry 34, head carriage 36, headgantry 38, z-axis motor 40, and a pair of x-y motors 42.

System casing 26 is a structural component of system 10 and may includemultiple structural sub-components such as support frames, housingwalls, and the like. In the shown embodiment, system casing 26 definesthe dimensions of bays 28, and of build chamber 30. Bays 28 arecontainer bays configured to respectively receive container portions 14of spool assemblies 12. Typically, each of bays 28 may be intended toreceive either a part material spool assembly 12 or a support materialspool assembly 12.

As shown, container portions 14 are loaded into bays 28 in their uprightorientations, such that spools retained within container portions 14(not shown in FIG. 1) each have an axis of rotation substantiallyaligned with a horizontal x-y plane. In the example shown in FIG. 1, thespools each have an axis of rotation substantially along the x-axis. Asdiscussed below, rotating the spools while container portions 14 areupright allow the spools to rotate in a hub-less manner with reducedfrictional resistance.

In the example shown in FIG. 1, the horizontal x-y plane is a horizontalplane defined by the x-axis and the y-axis, where the x-axis, they-axis, and the vertical z-axis are orthogonal to each other. The terms“about” and “substantially” are used herein with respect to measurablevalues and ranges due to expected variations known to those skilled inthe art (e.g., limitations and variabilities in measurements).

In an alternative embodiment, bays 28 may be omitted to reduce theoverall footprint of system 10. In this embodiment, container portions14 may stand upright adjacent to system casing 26, while providingsufficient ranges of movement for guide tubes 16 and print heads 18.Bays 28, however, provide convenient locations for loading spoolassemblies 12.

Build chamber 30 is an enclosed environment that contains platen 32 forprinting 3D part 22 and support structure 24. Build chamber 30 may beheated (e.g., with circulating heated air) to reduce the rate at whichthe part and support materials solidify after being extruded anddeposited (e.g., to reduce distortions and curling). In alternativeembodiments, build chamber 30 may be omitted and/or replaced withdifferent types of build environments. For example, 3D part 22 andsupport structure 24 may be built in a build environment that is open toambient conditions or may be enclosed with alternative structures (e.g.,flexible curtains).

Platen 32 is a platform on which 3D part 22 and support structure 24 areprinted in a layer-by-layer manner, and is supported by platen gantry34. In some embodiments, platen 32 may also include a flexible polymericfilm or liner on which 3D part 22 and support structure 24 are printed.Platen gantry 34 is a gantry assembly configured to move platen 32 along(or substantially along) the vertical z-axis and is powered by z-axismotor 40.

Head carriage 36 is a unit configured to receive one or more removableprint heads, such as print heads 18, and is supported by head gantry 38.Examples of suitable devices for head carriage 36, and techniques forretaining print heads 18 in head carriage 36, include those disclosed inSwanson et al., U.S. patent application Ser. No. 12/976,111; Swanson,U.S. Patent Application Publication No. 2010/0283172; and Swanson,International Publication No. WO2009/088995.

Head gantry 38 is a belt-driven gantry assembly configured to move headcarriage 36 (and the retained print heads 18) in (or substantially in) ahorizontal x-y plane above build chamber 30, and is powered by x-ymotors 42. Examples of suitable gantry assemblies for head gantry 38include those disclosed in Comb et al., U.S. patent Ser. No. 13/242,561.

As further shown in FIG. 1, system 10 may also include a pair of sensorassemblies 44, which, in the shown embodiment, are located adjacent tobays 28. Sensor assemblies 44 are configured to receive and retain guidetubes 16, while also providing sufficient ranges of movement for guidetubes 16 and print heads 18. Sensor assemblies 44 are also configured toread encoded markings from successive segments of the filaments movingthrough guide tubes 16. Examples of suitable devices for sensorassemblies 44 include those disclosed in Batchelder et al., U.S. PatentApplication Publication Nos. 2011/0117268, 2011/0121476, and2011/0233804.

System 10 also includes controller 46, which is one or moreprocessor-based controllers that may communicate over communication line47 with print heads 18, build chamber 30 (e.g., with a heating unit forbuild chamber 30), head carriage 36, motors 40 and 42, sensor assemblies44, and various sensors, calibration devices, display devices, and/oruser input devices. In some embodiments, controller 46 may alsocommunicate with one or more of bays 28, platen 32, platen gantry 34,head gantry 38, and any other suitable component of system 10.

While illustrated as a single signal line, communication line 47 mayinclude one or more electrical, optical, and/or wireless signal lines,allowing controller 46 to communicate with various components of system10. Furthermore, while illustrated outside of system 10, controller 46and communication line 47 may be internal components to system 10.

During operation, controller 46 directs z-axis motor 40 and platengantry 34 to move platen 32 to a predetermined height within buildchamber 30. Controller 46 then directs motors 42 and head gantry 38 tomove head carriage 36 (and the retained print heads 18) around in thehorizontal x-y plane above build chamber 30. Controller 46 may alsodirect print heads 18 to selectively draw successive segments of thefilaments from container portions 14 and through guide tubes 16,respectively.

Each print head 18 thermally melts the successive segments of thereceived filament such that it becomes a molten material, therebyallowing the molten material to be extruded and deposited onto platen 32for printing 3D part 22 and support structure 24 in a layer-by-layermanner. After the print operation is complete, the resulting 3D part 32and support structure 24 may be removed from build chamber 30, andsupport structure 24 may be removed from 3D part 22. 3D part 22 may thenundergo one or more additional post-processing steps.

As discussed above, spool assemblies 12 are removable and replaceablecontainer devices. As shown in FIG. 2, prior to a print operation, spoolassemblies 12 may be loaded to system 10 by individually removing spoolassemblies 12 from their packages. For example, each spool assembly 12may be retained in a box (e.g., box 48) during shipping and storage,where box 48 may include a variety of indicia and graphics foridentifying the material types contained in the respective spoolassembly 12 contained therein. While spool assembly 12 is retained inbox 48, guide tube 16 may be conveniently wrapped around and/or throughhandle 20, and print head 18 may be mounted to handle 20. In alternativeembodiments, guide tube 16 and/or print head 18 may be secured to one ormore retention mechanisms inside box 48. In additional alternativeembodiments, handle 22 may have a variety of different designs for auser to grasp, or may be omitted to a handle on box 48 (e.g., a handlecut or otherwise formed in box 48).

Container portion 14 of each spool assembly 12 includes wrapper bag 50,which is an example of a suitable sheath for container portion 14, andwhich is secured to handle 20. Wrapper bag 50 may be any suitablesheath, such as polymeric bags, wrappings (e.g., shrink wrap liner),metallic foil casings, and the like, which desirably prevent orsubstantially prevent ambient conditions from reaching the spooledfilament in container portion 14. For example, wrapper bag 50 may be amoisture-impermeable sheath to provide a moisture barrier, agas-impermeable sheath to provide a gas barrier, aparticulate-impermeable sheath to provide a dust barrier, and the like.

In the case of moisture-sensitive materials, the spooled filament isdesirably provided to print head 18 in a dry state (e.g., less than 300parts-per-million by weight of water) to prevent moisture fromnegatively affecting the extrusion process. As such, wrapper bag 50 mayprovide a moisture barrier for the filament during transportation,storage, and use in system 10.

Additionally, wrapper bag 50 may be deformable, as shown, to conform tothe dimensions of the components of container portion 14 that areretained within wrapper bag 50. In some embodiments, wrapper bag 50 mayalso be opaque to reduce light exposure (e.g., ultraviolet lightexposure), to reduce the risk of degrading the spooled filament overextended periods of storage.

After removal from box 48, the user may load spool assembly 12 into bay28 by lowering container spool assembly 12 into bay 28 in the shownupright orientation. Each spool assembly 12 includes locking arm 52slidably coupled to handle 20, and each bay 28 includes a pair ofopposing bay slots 54 configured to move locking arm 52 when spoolassembly 12 is loaded into bay 28. Briefly, locking arm 52 is anactuatable arm that engages with the spool (not shown in FIG. 2)retained within wrapper bag 50 to prevent the spool from rotating withinwrapper bag 50. This is beneficial during transportation and storage toprevent the filament from unraveling from the spool within containerportion 14 prior to use in system 10. Locking arm 52, however, does notpuncture or otherwise penetrate through wrapper bag 50 to preserve thebarrier from ambient conditions.

When spool assembly 12 is lowered into bay 28, locking arm 52 insertsinto bay slots 54 of bay 28, which press locking arm 52 upward todisengage locking arm 52 from the spool. This allows the spool to beunlocked in a hands-free manner when container portion 14 is loaded intobay 28. As can be appreciated, this hands-free disengagement of lockingarm 52 prevents system 10 from operating with spool assembly 12 in itslocked state. If this hands-free disengagement were otherwise omitted,and the user neglected to manually disengage locking arm 52, print head18 would have issues pulling the consumable filament from containerportion 14 since the spool would be locked against rotating.

Once loaded into bay 28, the user may remove guide tube 16 and printhead 18 from handle 20, and engage guide tube 16 through sensor assembly44. The user may then insert print head 18 into head carriage 36 asdiscussed in Swanson et al., U.S. patent application Ser. No.12/976,111. In alternative embodiments, the user may remove guide tube16 and print head 18 from handle 20, engage guide tube 16 through sensorassembly 44, and/or insert print head 18 into head carriage 36 prior toloading container portion 14 into bay 28.

As discussed in Swanson et al., U.S. patent application Ser. No.12/976,111; Swanson, U.S. Patent Application Publication No.2010/0283172; and Swanson, International Publication No. WO2009/088995,the filament in the loaded spool assembly 12 may be pre-fed throughguide tube 16, and into print head 18. In this embodiment, print head 18includes a filament drive mechanism for drawing successive segments ofthe consumable filament from container portion 14 and through guide tube16. As such, once each spool assembly 12 is loaded, system 10 may beginto use the filaments during one or more pre-printing operations (e.g.,calibration routines) or during print operations without requiring theuser to perform any additional loading tasks.

Spool assemblies 12 may remain loaded to system 10 until theyindividually exhaust their supplies of filaments, or until the userdecides to replace them for any desired reason (e.g., for printing withdifferent colors or compositions). Either spool assembly 12 may beunloaded from system 10 by removing print head 18 from head carriage 36,removing guide tube 16 from sensor assembly 44, and pulling containerportion 14 out of bay 28 by handle 20.

If the unloaded spool assembly 12 has exhausted its supply of theconsumable material filament, it is not necessary to re-engage lockingarm 52 with the spool retained within wrapper bag 50 (although, there isno harm in doing so). Instead, the empty spool assembly 12 may berecycled or otherwise discarded in an environmentally-friendly manner. Areplacement spool assembly 12 may then be loaded to system 10 followingthe same steps discussed above.

Alternatively, if the unloaded spool assembly 12 still retains a portionof its supply of the consumable filament, the user may re-engage lockingarm 52 with the spool retained within wrapper bag 50 to prevent thespool from rotating during storage. Additionally, in this situation, asegment of the consumable filament will remain extending through guidetube 16 and into print head 18. As such, when desired, the user mayreadily reload spool assembly 12 to system 10 following the same stepsdiscussed above for use in a new printing operation.

In the shown embodiment, container portion 14, guide tube 16, handle 20,and locking mechanism 52 of each spool assembly 12 are free ofelectronic components, such as filament drive mechanisms, motorizedspool-rotating mechanisms, electronic connectors to system 10, and thelike. Instead, all electronic components of spool assemblies 12 forcommunicating with system 10 and for feeding successive segments of thepart and support material filaments to system 10 are retained in printheads 18, such as discussed in Swanson et al., U.S. patent applicationSer. No. 12/976,111. In other embodiments, the electronic componentsneed not be limited to the print head portion of the spool assembly, andcould include, for example, wireless communications between the sealedspool and the system 10.

Spool assemblies 12 may alternatively remain in boxes 48 while beingloaded to bays 28. In this embodiment, upon loading a spool assembly12/box 48 into a bay 28, the user may pull locking arm 52 upward todisengage locking arm 52 from the spool retaining within wrapper bag 50.

Spool assemblies 12 and/or boxes 48 may also include indicators to allowusers to visually distinguish their contents. For example, print heads18, handles 20, and/or wrapper bags 68 may include indicia and/or colorsthat describe their retained filament materials. Bays 28 may alsoinclude corresponding indicia, such as indicia of “part material” and“support material”, and/or colors.

Furthermore, in the shown embodiment, print head 18 may be mounted toeither side of handle 20. For example, in the view shown in FIG. 2,print heads 18 are retained by the opposing sides of handles 20. Due tothis, spool assemblies 12 may appear as mirror images to each other,allowing the user to recognize which bay to load a particular spoolassembly 12 into.

As shown in FIG. 3, handle 20 is fabricated from opposing handlesections 56 and 58, which are secured together around a top portion ofwrapper bag 50. Handle sections 56 and 58 are rigid componentsfabricated from one or more polymeric and/or metallic materials, anddefine handle opening 60, lock slot 62, holsters 64 and 66, and tubechannel 68.

Handle opening 60 is an opening for a user to extend his or her handthrough to grip handle 20. The location of handle 20 relative tocontainer portion 14 allows container portion 14 to be suspended in itsupright orientation, as shown, such as when the user grips handle 20 athandle opening 60. Thus, container portion 14 may be convenientlylowered into bay 28 in its upright orientation.

Lock slot 62 is an elongated slot that extends vertically when containerportion 14 is upright, where locking arm 52 is slidably coupled tohandle 20 at lock slot 62. In particular, locking arm 52 includes alaterally-extending collarbone member 70, a pair of downward-extendingappendages 72 a and 72 b that extend downward from the opposing ends ofcollarbone member 70, and a pair of contact tips 74 a and 74 b at thebottom ends of appendages 72 a and 72 b (appendage 72 b and contact tip74 b are not shown in FIG. 3). As discussed below, collarbone member 70is configured to slide up and down within lock slot 62 to respectivelydisengage and engage contact tips 74 a and 74 b with opposing sides ofthe spool (not shown in FIG. 3) retained within wrapper bag 50.

Holster 64 is a first rigid housing configured to protect print head 18when retained by handle 20, as shown. In the shown example, print head18 includes cartridge assembly 76 and liquefier pump assembly 78, wherecartridge assembly 76 is mounted to handle 20 and liquefier pumpassembly 78 is inserted within holster 64. This arrangement allows theuser to grip handle 20 through handle opening 60 without damaging a tipend of liquefier pump assembly 78.

Holster 66 is a second rigid housing, which, optionally, allows printhead 20 to be mounted to the opposing side of handle 20. This allowsprint head 20 to be retained on either side of handles 22, as shownabove in FIG. 2.

Tube channel 68 extends through the top portion of handle 20, betweenhandle sections 56 and 58, and provides a convenient location to retainguide tube 16, as shown. As such, a first end of guide tube 16 extendswithin container portion 14, and a second end of guide tube 16 extendswithin cartridge assembly 76 of print head 18. The middle portion ofguide tube 16 between its first and second ends may then be woundthrough tube channel 68 for transportation and storage.

FIGS. 4A-4C illustrate a suitable process for manufacturing spoolassembly 12. As shown in FIG. 4A, the process involves inserting module80 into opening 82 of wrapper bag 50. Further discussion of module 80and how it may be manufactured is provided below. Briefly, module 80includes shell 84, spool 86, and eyelet seal 88, where spool 86 includesa supply of filament 90 (typically, a moisture-sensitive material), and,in the embodiment shown, is rotatably retained within shell 84. Eyeletseal 88 is a seal component that extends through shell 84 and provides asealed pathway for guide tube 16 (and for filament 90 extending throughguide tube 16).

As shown in FIG. 4B, after module 80 is inserted into wrapper bag 50,the walls of wrapper bag 50 at opening 82 may then be sealed together toform sealed tab 92. Sealed tab 92 extends from the body of wrapper bag50 in which module 80 resides (referred to as body 94), such that sealedtab 92 may be punctured or otherwise penetrated without breaking theseal of wrapper bag 50 at body 94. As further shown, eyelet seal 88extends through sealed tab 92 to maintain the seal around guide tube 16,and to operably couple a retaining portion of guide tube 16 to wrapperbag 50. In other embodiments, eyelet seal 88 may be omitted and theretaining portion of guide tube 16 may otherwise be operably coupled towrapper bag 50, for example, by application of a hot melt adhesive.

In alternative embodiments, wrapper bag 50 may be formed around module80 using a variety of different techniques. For example, wrapper bag 50may be wrapped around module 80 and sealed (e.g., shrink wrapped). Inthese alternative embodiments, wrapper bag 50 desirably retains anupward-extending tab corresponding to sealed tab 92, which may bepunctured or otherwise penetrated without breaking the seal of wrapperbag 50 at body 94.

Handle sections 56 and 58 include reciprocating fasteners 96 forsecuring handle sections 56 and 58 together. This may be accomplished bypositioning handle sections 56 and 58 on opposing sides of sealed tab92, as illustrated by arrows 98, and inserting collarbone member 70 oflocking arm 52 into the slot halves of lock slot 62 of handle sections56 and 58 (referred to as slot halves 62 a and 62 b). Handle sections 56and 58 may then be secured together with reciprocating fasteners 96.When fastened together, reciprocating fasteners 96 puncture throughsealed tab 92 to securely suspend container portion 14 from handle 20 bysealed tab 92.

In one embodiment, sealed tab 92 may be pre-punctured at the intendedlocations of reciprocating fasteners 96 to allow reciprocating fasteners96 to be easily inserted through the pre-punctured openings. However, ineither case, the seal of sealed tab 92 extends below any of thepunctures of reciprocating fasteners 96, thereby maintaining the seal ofwrapper bag 50 at body 94.

Handle sections 56 and 58 also respectively include mounting pegs 100and 102. Mounting pegs 100 and 102 are lateral pegs or other suitablefeatures that are positioned to mount print heads (e.g., print heads 18)on either side of handle 20.

As shown in FIG. 4C, when secured together to form handle 20, handlesections 56 and 58 are partially offset from each other to define tubechannel 68. Handle 20 also includes a pair of adjacent apertures 104 andcooling port 106. Apertures 104 are openings through handle 20 forreducing the weight of handle 20, and may also assist in increasingcooling air flow around print head 18 when print head 18 is mounted tohandle 20. Cooling port 106 is an additional opening for allowingcooling air to flow around liquefier pump assembly 78 when liquefierpump assembly 78 is inserted into holster 64. For example, cooling port106 may align with cooling vents of liquefier pump assembly 78.

After handle sections 56 and 58 are secured together, locking arm 52 maybe pressed downward to the bottom of lock slot 62 to engage with spool86 of module 80 retained within wrapper bag 50 and shell 84. Guide tube16 may also be wound through channel 68 and print head 18 may beinserted into holster 64 and mounted to mounting pegs 100, such as shownabove in FIG. 3.

In the shown embodiment, cartridge assembly 76 of print head 18 has anon-symmetrical design that includes a generally flat side. Depending onthe positioning of liquefier pump assembly 78 in print head 20, printhead 20 may be either configured for insertion into holster 64 orholster 66. As discussed in Swanson et al., U.S. patent application Ser.No. 12/976,111, the mirror-image designs of print heads 18 may assistusers in determining where to insert the respective print heads 18 intohead carriage 36 (i.e., to prevent reverse order insertions).

FIGS. 5A, 5B, 6A, and 6B illustrate the operation of locking arm 52 toengage and disengage with spool 86 retained within wrapper bag 50 (spool86 illustrated with hidden lines). As discussed further below, spool 86includes multiple holes or indentations 108 and 110 (illustrated withhidden lines) extending radially around opposing flanges of spool 86.

FIGS. 5A and 5B respectively show the opposing sides of handle 20 withlocking arm 52 engaged with both sides of spool 86. In this lockedstate, collarbone member 70 of locking arm 52 is positioned at thebottom of lock slot 62, which engages contact tips 74 a and 74 b withindentations 108 and 110 of spool 86 (through wrapper bag 50 and shell84), as discussed below. To unlock spool 86, collarbone member 70 israised upward through lock slot 62 until contact tips 74 a and 74 bdisengage from spool 86, as illustrated by arrows 112 in FIGS. 5A and5B.

For example, as spool assembly 12 is lowered into bay 28 (shown in FIGS.1 and 2) in its upright orientation, contact tips 74 a and 74 b oflocking arm 52 engage ledges of the opposing bay slots 54 (shown in FIG.2). Upon reaching the ledges of bay slots 54, the continued downwardmovement of spool assembly 12 into bay 28 pushes locking arm 52 upwardin lock slot 62, as illustrated by arrows 112.

As shown in FIGS. 6A and 6B, this positions collarbone member 70 at oradjacent to the top of lock slot 62, and allows spool 86 to rotatewithin shell 84, as illustrated by arrows 115. To re-engage locking arm52 with spool 86, collarbone member 70 may be lowered through lock slot62 until contact tips 74 a and 74 b re-engage with indentations 108 and110 (through wrapper bag 50 and shell 84), as illustrated by arrows 116.Spool 86 may be rotated by a small amount to fully engage contact tips74 a and 74 b with indentations 108 and 110. This locks spool 86 andprevents further rotation.

The engagements and disengagements of locking arm 52 with spool 86, asshown above in FIGS. 5A, 5B, 6A, and 6B occur through wrapper bag 50.The deformable nature of wrapper bag 50 allows wrapper bag 50 to conformto the locking engagement between contact tips 74 a and 74 b of lockingarm 52 and indentations 108 and 110 of spool 86. Therefore, wrapper bag50 may remain intact (i.e., not punctured or otherwise penetrated)during the engagements between locking arm 52 and spool 86, therebypreserving the barrier from ambient conditions.

FIGS. 7 and 8 further illustrate spool assembly 12 with wrapper bag 50omitted for ease of discussion. As shown in FIG. 7, shell 84 and spool86 of module 80 are disposed below handle 20, and locking arm 52 isengagable with spool 86 through shell 84. In the shown embodiment,however, shell 84 is not directly connected to handle 20. Rather, asdiscussed above, handle 20 is secured to sealed tab 92 of wrapper bag 50(shown in FIG. 4B), where wrapper bag 50 retains shell 84 and spool 86.

Shell 84 includes right shell section 118 and left shell section 120,which, in the shown embodiment, are identical rigid structuresfabricated from one or more polymeric and/or metallic materials. Shellsections 118 and 120 are secured together to rotatably retain andprotect spool 86 in a hub-less manner. Right shell section 118 includescentral opening 122 and inwardly-extending posts 124 at its base end.Central opening 122 is an opening into shell 84 through which spool 86may be viewed, and includes inwardly-extend rim 126.

Spool 86 is a hub-less spool that includes hollow shaft 128 and flange130. Hollow shaft 128 is a filament-receiving shaft that is visiblethrough central opening 122 of right shell section 118. Hollow shaft 128has a hollow interior that is bisected by middle wall 132, where middlewall 132 provides structural support for spool 86. Flange 130 extendsfrom a first end of hollow shaft 128 facing right shell section 118, andincludes indentations 108 extending radially around its outer perimeter.

As shown in FIG. 8, left shell section 120 includes central opening 134and inwardly-extending posts 136 at its base end, which are identical tocentral opening 122 and posts 124 of right shell section 118. Centralopening 134 includes inwardly-extend rim 138, which is identical toinwardly-extend rim 126 of right shell section 118. Spool 86 alsoincludes flange 140, which extends from a second end of hollow shaft 128facing left shell section 120, and includes indentations 110 extendingradially around its outer perimeter.

Rims 126 and 138 are suitable for aligning spool 86 with shell sections118 and 120 when manufacturing module 80. However, as discussed below,in the shown embodiment, spool 86 desirably does not rest on rims 126and 138 when spool assembly 12 is positioned upright. Rather, spool 86rests on a pair of bearing rollers (shown below in FIG. 11) mounted onposts 124 and 136, which reduces the contact surface area between spool86 and shell 84, and hence, reduces frictional resistance.

Reduced friction of rotating spool 86 is beneficial to reduce thepulling force required by print head 18 to draw the successive segmentsof filament 90, as well as reducing the variations in the requiredpulling force. Variations in the pulling force may affect the responsetimes that print head 18 relies upon for accurately melting andextruding the consumable material from filament 90, which can affect theaccuracy of the printing operation. In alternate embodiments, spool 86may rest on and rotate around a hub within shell 84, and, in suchembodiments, posts 124 and 136, along with the bearing rollers, may beomitted.

FIGS. 9 and 10 are expanded views of the engagements between locking arm52 and spool 86 through shell sections 118 and 120, respectively. Asshown in FIG. 10, contact tip 74 a of locking arm 52 may engageindentations 108 of flange 130 through the top end of right shellsection 118. In particular, right shell section 118 includes recessednotch 142, which itself includes engagement opening 144 and side slots146. Engagement opening 144 is an opening through right shell section118 for access to indentations 108. Side slots 146 are located onopposing sides of engagement opening 144, and are configured to retainflexure tab 148.

In the shown example, flexure tab 148 is an M-shaped component derivedfrom one or more polymeric and/or metallic materials. For example, asshown, flexure tab 148 includes three prongs, namely outer prongs 150and central prong 152. Outer prongs 150 are configured to slide withinside slots 146 for retaining flexure tab 148 in recessed notch 142 witha frictional fit and/or with an adhesive.

Central prong 152 extends across engagement opening 144 and may beflexed inward through engagement opening 144 by contact tip 74 a. In theshown embodiment, contact tip 74 a extends inwardly at an angle fromappendage 72 a, thereby being configured to press central prong 152inward through engagement opening 144. When flexed inward throughengagement opening 144, central prong 152 also extends into one ofindentations 108 to prevent spool 86 from rotating.

As shown in FIG. 10, contact tip 74 b of locking arm 52 may engageindentations 110 of flange 140 through the top end of left shell section120. In particular, left shell section 120 includes recessed notch 154,which itself includes engagement opening 156 and side slots 158.Engagement opening 156 and side slots 158 may function in the samemanner as engagement opening 144 and side slots 146 (shown in FIG. 9)for retaining flexure tab 160. In the shown embodiment, engagementopening 156 is aligned directly opposite of engagement opening 144, suchthat each are simultaneously engaged by contact tips 74 a and 74 b,providing redundancy in operation. In an embodiment, engagement openings144 and 156 may be offset from one another such that only one is engagedat a given time. In a further alternate embodiment, spool 86 may have anindentations on only a single flange (e.g., either indentations 108 or110).

Flexure tab 160 is a second M-shaped component that is identical toflexure tab 148, and includes outer prongs 162 and central prong 164.Outer prongs 162 are configured to slide within side slots 158 forretaining flexure tab 160 in recessed notch 154 with a frictional fitand/or with an adhesive. Central prong 164 functions in the same manneras central prong 152 of flexure tab 148, and may be flexed inwardthrough engagement opening 156 by contact tip 74 b. In the shownembodiment, contact tip 74 b also extends inwardly at and angle fromappendage 72 b, thereby being configured to press central prong 164inward through engagement opening 156. When flexed inward throughengagement opening 156, central prong 164 extends into one ofindentations 110 to prevent spool 86 from rotating.

Flexure tabs 148 and 160 increase the ease at which locking arm 52disengages from spool 86 when spool assembly 12 is loaded into bay 28,while also preventing locking arm 52 from prematurely disengaging fromspool 86, such as during transportation or storage. As shown in FIGS. 9and 10, central prongs 152 and 164 provide smooth surfaces for contacttips 74 a and 74 b to travel along when locking arm 52 is pressed upwardthrough lock slot 62 of handle 20. This reduces the force required todisengage contact tips 74 a and 74 b from indentations 108 and 110, andto move locking arm 52 upward through lock slot 62. Without flexure tabs148 and 160, contact tips 74 a and 74 b may become mechanically stuckwithin engagements openings 144 and 156, which could prevent contacttips 74 a and 74 b from disengaging from spool 86 when spool assembly 12is loaded into bay 28.

Flexure tabs 148 and 160 may be manufactured from one or more materialshaving shape memory and/or may be inherently biased outward and awayfrom engagements openings 144 and 156. This allows central prongs 152and 164 to bend back by sufficient amounts to fully exit indentations108 and 110 when contact tips 74 a and 74 b disengage. Otherwise,central prongs 152 and 164 may undesirably remain engaged withindentations 108 and 110, preventing spool 86 from rotating even whenlocking arm 52 is disengaged. This inherent biasing also preventslocking arm 52 from sliding down under gravity by requiring a minimalamount of pressure to overcome the bias (greater than attainable bygravity itself). This prevents locking arm 52 from unintentionallylocking spool 86, such as during a printing operation with system 10.

As further shown in FIGS. 9 and 10, right shell section 118 includesoverhang lip 165 a (shown in FIG. 9) and left shell section 120 includesoverhang lip 165 b (shown in FIG. 10). Overhang lip 165 a is disposedover recessed notch 142, and in particular, over flexure tab 148.Similarly, overhang lip 165 b is disposed over recessed notch 154 andflexure tab 160. Overhang lips 165 a and 165 b prevent flexure tabs 148and 160 from dislodging from recessed notches 142 and 154 when lockingarm 52 is disengaged. Otherwise, without overhang lips 165 a and 165 b,flexure tabs 148 and 160 may be pulled out of recessed notches 142 and154, and fall down into wrapper bag 50.

In an alternative embodiment, locking arm 52 may directly engage withindentations 108 and 110 without the use of flexure tabs 148 and 160. Inthis embodiment, locking arm 52 is desirably configured to release fromindentations 108 and 110 and engagements openings 144 and 156 withoutrequiring undue force. For example, contact tips 74 a and 74 b mayinclude sloped surfaces that extend through engagements openings 144 and156 and into indentations 108 and 110 when engaged. Accordingly, theterms “operably engage”, “operable engagement”, and the like, withreference to locking arm 52 and spool 86, refer to indirect engagements(e.g., with flexure tabs 148 and 160) and to direct engagements.

FIG. 11 further illustrates spool assembly 12 with handle 20, wrapperbag 50, locking arm 52, filament 90, and right shell section 118 omittedfor ease of discussion. As shown, guide tube 16 has a first end 166 thatextends within shell 84, and a second end (not shown) disposed withincartridge assembly 76 of print head 18. First end 166 of guide tube 16remains secured within shell 84 with eyelet seal 88.

Spool 86 rotates in the direction of arrow 115 around axis 168, where,when spool assembly 12 is upright, axis 168 is substantially aligned ina horizontal plane. Flanges 130 and 140 of spool 86 also respectivelyinclude perimeter edges 170 and 172, which are the outer annular edgesof flanges 130 and 140.

Module 80 also includes bearing rollers 174, which are located at thebase of shell 84 on posts 124 and 126 (shown in FIGS. 7 and 8) forsupporting perimeter edges 170 and 172 of spool 86, and may rotatearound axes 176. Axes 176 are substantially parallel to each other andto axis 168, but are not co-linear with each other or with axis 168.Bearing rollers 174 may be fabricated from one or more polymeric and/orplastic materials, and allow spool 86 to rotate around axis 168 withonly two contact points on each of perimeter edges 170 and 172. Inalternative embodiments, bearing rollers 174 may be replaced with avariety of different bearing supports, such as a pair of non-rotatablebearing shafts that extend along axes 176 between shell sections 118 and120.

FIGS. 12 and 13 are respective interior views of right shell section 118and left shell section 120, where spool 86 and bearing rollers 174 areomitted for ease of discussion. A comparison of FIGS. 12 and 13 showthat right shell section 118 and left shell section 120 are identicalstructures. As shown in FIG. 12, right shell section 118 includesinterior region 178. Similarly, as shown in FIG. 13, left shell section120 includes interior region 180. When right shell section 118 and leftshell section 120 are secured together to form shell 84, interiorregions 178 and 180 define a combined volume of shell 84 to retain spool86 and bearing rollers 174.

Spool 86, retained within the combined volume defined by interiorregions 178 and 180, is supported by bearing rollers 174 in a hub-lessmanner. As shown, posts 124 and 136 (which retain bearing rollers 174)are radially offset from each other by about angle 182, based on an axisof rotation of spool 86 (i.e., axis 168, shown in FIG. 11). Examples ofsuitable angles for angle 182 range from about 75 degrees to about 105degrees, with particularly suitable angles ranging from about 85 degreesto about 95 degrees (e.g., about 90 degrees, as shown in FIGS. 12 and13). These suitable angles provide sufficient bearing support forrotating spool 86 with reduced contact surface area when spool assembly12 is upright (e.g., as shown in FIGS. 1-3).

Two bearing rollers or supports provide a particularly suitable supportarrangement for spool 86. However, in alternative embodiments, spoolassembly 12 may include additional numbers of bearing rollers orsupports. In further alternate embodiments, bearing rollers 174 may bereplaced with non-rotatable bearing supports that each provide afriction-reduced surface on which perimeter edges 170 and 172 of flanges130 and 140 may rotate.

Additionally, when secured together, the bottom corners of right shellsection 118 and left shell section 120 (respectively referred to ascorner regions 184 a and 184 b in FIGS. 12 and 13) are walled off fromthe interior volume of shell 84 and bearing rollers 174 to define a pairof corner compartments. These corner compartments within shell 84 areconvenient locations for storing items, such as desiccant packages formaintaining a low-moisture environment within container portion 14,identification chips (e.g., RFID chips), and the like.

Also when secured together, the top corners of right shell section 118and left shell section 120 (respectively referred to as corner regions186 a and 186 b in FIGS. 12 and 13) define a slot and an offset regionfor eyelet seal 88. As shown in FIG. 14, corner regions 186 a and 186 bdefine slot 188 and offset region 190, where slot 188 is accessible tooffset region 190 through opening 192, and is accessible to the exteriorof shell 84 through opening 194.

As further shown, eyelet seal 88 is secured to shell 84 at slot 188,where eyelet seal 88 includes base portion 196 and extension portion198. Base portion 196 and extension portion 198 are each rigidcomponents fabricated from one or more polymeric and/or metallicmaterials. Base portion 196 is the component of eyelet seal 88 securedin slot 188, and extension portion 198 extends out of shell 84 throughopening 194.

Guide tube 16 correspondingly extends through extension portion 198,base portion 196, and opening 192, such that inlet end 166 of guide tube16 is located within offset region 190. Offset region 190 allows inletend 166 of guide tube 16 to be positioned at a suitable offset locationrelative to spool 86 to receive the successive segments of filament 90from spool 86 as spool 86 rotates.

FIGS. 15 and 16 further illustrate eyelet seal 88 and its engagementwith guide tube 16. As shown in FIG. 15, eyelet seal 88 also includesretention clip 200 mounted to base portion 196, where guide tube 16extends through extension portion 198 and base portion 196, and furtherthrough retention clip 200. Retention clip 200 is configured to allowguide tube 16 to be readily inserted into container portion 14, butreduces the ability pull guide tube 16 back out of container portion 14.This reduces the risk of guide tube 16 becoming detached from containerportion 14, which can potentially break the seal of container portion14.

As shown in FIG. 16, eyelet seal 88 may also include gasket seal 202,which is disposed between base portion 196 and retention clip 200. Guidetube 16 exits the inner conduit or channel of extension portion 198 andbase portion 194 (referred to as inner conduit 204), and is alsoinserted through gasket seal 202. Gasket seal 202 accordingly assists inmaintaining the barrier from ambient conditions within container portion14 during transportation, storage, and use of spool assembly 12.

Extension portion 198 of eyelet seal 88 has a generally flat, taperedgeometry compared to the cylindrical geometry of guide tube 16. Thisallows wrapper bag 50 to be collapsed around extension portion 198 toform seal tab 92 (shown in FIG. 4B) in a manner that provides a goodseal around extension portion 198. Inner conduit 204 accordingly has afirst opening within shell 84 (i.e., at gasket seal 202) and a secondopening located outside of wrapper bag 50. While guide tube 16 and innerconduit 204 are illustrated with cylindrical inner diameters, inalternative embodiments, guide tube 16 and inner conduit 204 may exhibitnon-cylindrical inner cross-sections (e.g., rectangular cross-sectionsfor use with ribbon filaments).

Additionally, the rigid nature of extension portion 198 prevents guidetube 16, which is relatively flexible, from collapsing under the seal atseal tab 92. Thus, spool assembly 12 provides a convenient and effectivemechanism for delivering consumable filaments, while also maintaining abarrier from ambient conditions during transportation, storage, and usein system 10.

In alternative embodiments, spool assemblies 12 may incorporate housingstructures (e.g., shell 84) having a variety of different designs, whilealso allowing the spools to rotate in hub-less manners. For example,FIG. 17 illustrates spool assembly 312, which corresponds to spoolassembly 12, and where corresponding reference numbers are increased by“300” from those of spool assembly 12.

In this embodiment, spool assembly 312 includes half-moon housingstructure 384 in lieu of shell 84. Housing structure 384 includes aU-shaped cavity 506 between a pair of side walls (only a single sidewall is shown in FIG. 17, as illustrated by broken line 508). The baseof cavity 506 includes bearing supports 424, which are non-rotatablebearing supports corresponding to bearing rollers 174 of spool assembly12. In alternative embodiments, bearing supports 504 may be rotatable inthe same manner as bearing rollers 174.

During assembly, spool 386 may be inserted into cavity 506 until theflange perimeter edges (e.g., perimeter edge 470) rests on bearingsupports 474. In this case, the top half of spool 386 extends abovehousing structure 384, such that housing structure 384 encases only aportion of spool 386. The combined housing structure 384/spool 386 maythen be inserted into wrapper bag 350 and sealed to form a sealed tab(not shown) corresponding to sealed tab 92. Additionally, an eyelet seal(not shown) retaining guide tube 316 may be secured with the sealed tab.However, in this embodiment, the eyelet seal is not retained by housingstructure 384. In an alternative embodiment, the eyelet seal may beomitted.

Handle 320 may then be secured to the sealed tab, and guide tube 316 andprint head 318 may be mounted to handle 320 in the same manner asdiscussed above for spool assembly 12. Additionally, locking arm 352 mayengage indentations 408 and 410 of spool 386 to prevent spool 386 fromrotating relative to frame structure 384. In this case, since framestructure 384 does not encase spool 386 at the engagement locations withlocking arm 352, contact tips 374 a and 374 b of locking arm 352directly engage indentations 408 and 410 without the use of flexuretabs. Locking arm 352 also desirably does not puncture or otherwisepenetrate wrapper bag 350 during use to maintain the barrier fromambient conditions.

Spool assembly 312 may be used in system 10 in the same manner as spoolassembly 12. The rotation of spool 386 with the use of bearing supports474 also reduces the contact surface area between spool 386 and framestructure 384, thereby reducing frictional resistance. Accordingly, thespool assemblies of the present disclosure may include containerportions having a variety of different components that allowfilament-containing spools to rotate with reduced frictional resistance,and to engage with locking mechanisms through sheaths (e.g., wrapperbags) without puncturing or otherwise penetrating the sheaths.

The spool assemblies of the present disclosure (e.g., spool assemblies12 and 312) may be used to deliver a variety of different part andsupport material filaments. Examples of suitable filaments for use inthe spool assemblies of the present disclosure include those disclosedand listed in Crump et al., U.S. Pat. No. 5,503,785; Lombardi et al.,U.S. Pat. Nos. 6,070,107 and 6,228,923; Priedeman et al., U.S. Pat. No.6,790,403; Comb et al., U.S. Pat. No. 7,122,246; Batchelder, U.S. PatentApplication Publication No. 2009/0263582; Hopkins et al., U.S. PatentApplication Publication No. 2010/0096072; Batchelder et al., U.S. PatentApplication Publication No. 2011/0076496; and Batchelder et al., U.S.Patent Application Publication No. 2011/0076495. Furthermore, thefilaments may each include encoded markings, as disclosed in Batchelderet al., U.S. Patent Application Publication Nos. 2011/0117268,2011/0121476, and 2011/0233804, which may be used with sensor assemblies44 of system 10.

Although the present disclosure has been described with reference topreferred embodiments, workers skilled in the art will recognize thatchanges may be made in form and detail without departing from the spiritand scope of the disclosure.

1-20. (canceled)
 21. A method for loading a spool assembly to anadditive manufacturing system, the method comprising: providing a spoolassembly comprising a rotatable spool with a filament supply thereon andhaving a locking mechanism configured to engage with the spool toprevent rotation of the spool during transport or storage of the spoolassembly; engaging the locking mechanism with the spool to preventrotation of the spool; inserting the spool assembly into a bay of theadditive manufacturing system wherein the locking mechanism engages witha surface of the bay to disengage the locking mechanism from the spool;and feeding the filament to a print head retained by the additivemanufacturing system by rotating spool after the locking mechanism isdisengaged from the spool while the spool is in the bay of the additivemanufacturing system.
 22. The method of claim 21, and further comprisingencasing the spool in a sealed sheath wherein the locking mechanismengages the spool through the sealed sheath to prevent rotation of thespool.
 23. The method of claim 21, and further comprising engaging thelocking mechanism with one or more slots in the bay when inserting thespool assembly into the bay such that one or more slots displace thelocking mechanism from the spool in a hands-free manner.
 24. The methodof claim 21, and further comprising providing a handle having a handleslot configured for slidably coupling the locking mechanism to thehandle.
 25. The method of claim 24, wherein inserting the spool assemblyinto the bay slides the locking mechanism within the handle slot todisengage the locking mechanism from the spool allowing the spool torotate for feeding the filament to the print head when the spool isinserted into the bay.
 26. The method of claim 21, and furthercomprising: removing the spool assembly from the bay of the additivemanufacturing system; and operably re-engaging the locking mechanismwith the spool of the removed spool assembly.
 27. The method of claim22, wherein the sealed sheath provides a moisture barrier to the encasedspool.
 28. The method of claim 21, wherein the spool comprises a shaftextending along an axis of rotation of the spool and a flange extendingfrom the shaft, the flange comprising a plurality of indentations oropenings extending radially around the flange, and wherein disengagingthe locking mechanism from the spool comprises operably disengaging aportion of the locking mechanism from the one indentation or opening.29. A method for loading a spool assembly to an additive manufacturingsystem, the method comprising: providing a spool assembly comprising aspool retaining a filament, wherein the spool is retained within asealed sheath that defines a barrier for the retained spool; engagingthe spool with a locking mechanism of the spool assembly to preventrotation of the spool assembly; inserting the spool assembly into a bayof the additive manufacturing system; contacting the locking mechanismwith a surface of the bay while inserting the spool assembly into thebay; and displacing the contacted locking mechanism with the surface ofthe bay while inserting the spool assembly into the bay to disengage tothe locking mechanism from the spool; and feeding filament from thespool to a print head retained by the additive manufacturing system byrotating the spool within the sealed sheath after the locking mechanismis disengaged from the spool.
 30. The method of claim 29, wherein thelocking mechanism operably engages the spool through the sealed sheath.31. The method of claim 29, wherein the sealed sheath provides amoisture barrier to the encased spool.
 32. The method of claim 29, andfurther comprising feeding the filament from the spool to the print headthrough a flexible tube that has a first end disposed within the sealedsheath and a second end coupled to the extrusion head, wherein themoisture barrier of the sealed sheath remains intact during the feedingstep.
 33. The method of claim 29, and further comprising: removing thespool assembly from the bay of the additive manufacturing system; andoperably re-engaging the locking mechanism with the spool of the removedspool assembly.
 34. The method of claim 29, wherein the spool comprisesa shaft extending along an axis of rotation of the spool and a flangeextending from the shaft, the flange comprising a plurality ofindentations or openings extending radially around the flange, andwherein disengaging the locking mechanism from the spool comprisesoperably disengaging a portion of the locking mechanism from one or moreof the plurality of inventions or openings.
 35. The method of claim 34,wherein operably disengaging the portion of the locking mechanism fromone of the plurality of indentations or openings comprises disengagingthe portion of the locking mechanism from a flexure tab, whichdisengages the flexure tab from the one indentation or opening.
 36. Amethod for loading a spool assembly to an additive manufacturing system,the method comprising: providing a spool assembly comprising a spoolretaining a filament, wherein the spool is retained within a sealedsheath of the spool assembly that defines a barrier for the retainedspool; engaging the spool with a locking mechanism of the spool assemblyto prevent the spool from rotating in the sealed sheath; inserting thespool assembly into a bay of the additive manufacturing system, whichdisengages the locking mechanism in a hands-free manner; removing thespool assembly from the bay of the additive manufacturing system; andoperably re-engaging the locking arm with the spool of the removed spoolassembly.
 37. The method of claim 36, and further comprising engagingthe locking mechanism with one or more surfaces in the bay wheninserting the spool assembly into the bay such that surfaces displacethe locking mechanism for automatically disengaging the lockingmechanism from the spool in the hands-free manner.
 38. The method ofclaim 37, wherein the spool comprises a shaft extending along an axis ofrotation of the spool and a flange extending from the shaft, the flangecomprising a plurality of indentations or openings extending radiallyaround the flange, and wherein disengaging the locking mechanism fromthe spool comprises operably disengaging a portion of the lockingmechanism from the one indentation or opening.
 39. The method of claim38, wherein operably disengaging the portion of the locking mechanismfrom one of the plurality of indentations or openings comprisesdisengaging the portion of the locking mechanism from a flexure tab,which disengages the flexure tab from the one indentation or opening.